[Bf-blender-cvs] [65d4c58060e] blender-v3.1-release: Fix Cycles assert in debug mode after recent changes

[Brecht Van Lommel]

Commit: 65d4c58060eae4f544e4e483a38ca2b8d30bd707
Author: Brecht Van Lommel
Date:   Mon Feb 14 15:33:47 2022 +0100
Branches: blender-v3.1-release
https://developer.blender.org/rB65d4c58060eae4f544e4e483a38ca2b8d30bd707

Fix Cycles assert in debug mode after recent changes

We sometimes call start() on already started renders, just do nothing then.

Ref D14086

===================================================================

M	intern/cycles/session/session.cpp

===================================================================

diff --git a/intern/cycles/session/session.cpp b/intern/cycles/session/session.cpp
index f6e06f20aba..8fcb5c9ac96 100644
--- a/intern/cycles/session/session.cpp
+++ b/intern/cycles/session/session.cpp
@@ -110,7 +110,10 @@ void Session::start()
   {
     /* Signal session thread to start rendering. */
     thread_scoped_lock session_thread_lock(session_thread_mutex_);
-    assert(session_thread_state_ == SESSION_THREAD_WAIT);
+    if (session_thread_state_ == SESSION_THREAD_RENDER) {
+      /* Already rendering, nothing to do. */
+      return;
+    }
     session_thread_state_ = SESSION_THREAD_RENDER;
   }